There is a growing interest in delivering drugs, proteins, peptides and stem cells or other diagnostic or therapeutic active agents to the brain and central nervous system intranasally, known as nose to brain delivery. Conventional systemic delivery of agents intended for activity in the brain is problematic because drugs in the general circulation must bypass the blood brain barrier in order to reach the brain. This necessitates high dose levels to achieve results and increased side effects. Direct delivery to the brain or spinal cord through intracerebroventricular or intraparenchymal injection is invasive, involves higher risk and is expensive. Direct injections become much more difficult when multiple treatments are required.
A number of drugs, proteins, peptides and stem cells have been shown to be active in human and animal brains when administered nasally, including insulin, deferoxamine, progesterone, L-dopa and Glial cell-line derived neurotrophic factor (GDNF) among others. Delivery of powders or liquid formulated active agents has been accomplished by drops, atomizing or inhalation devices, however the most effective, or most convenient method of administration is by nasal delivery of an aerosol, spray stream or mist to the cribriform plate, olfactory and trigeminal neuronal pathways.
There is a need, therefore, for packaging and delivery devices for measured dosages of active agent(s) in which the liquid or powder components of the agent(s) can be stored with a long and sterile shelf life, either in separate chambers and then mixed with a liquid or another active agent just prior to use, or in single or multiple chambers of the same components for convenient delivery of multiple doses or applications, and in particular for delivery to the brain in a non-invasive, safe and relatively economical manner.